Patent GB-814198-A (GB)
Title: New thiophosphoric acid esters and their use in the control of pests
IPC: A01N57/10
Filed: 1955-07-07
Abstract: The invention comprises compounds of the general formula <FORM:0814198/IV (b)/1> in which one Z represents sulphur and the remaining Z's represent oxygen, R represents an alkyl radical containing not more than 4 carbon atoms and R1 represents a cycloaliphatic e.g. cyclohexyl, or araliphatic radical e.g. benzyl, or a radical of a heterocyclic compound free from enolisable ketone or thio ketone groups, e.g. tetrahydrofurfuryl, R2 represents an aliphatic radical which may be substituted with halogen thiocyanogen cyano, nitro ether or ester group and "alkeylene" represents an alkylene radical containing not more than 4 carbon atoms.  They may be prepared by reacting a compound of the general formula <FORM:0814198/IV (b)/2> with a compound of the general formula Hal-alkylene-S-R2, or a compound of the general formula <FORM:0814198/IV (b)/3> with one of the general formula R1-Hal. R, R1, R2 and "alkylene" having the meanings given above and Me representing a metal atom, or by the additive combination of sulphur with a derivative of phosphorous acid of the general formula <FORM:0814198/IV (b)/4> Examples are given of the preparation of (1) tetra - hydro - furfuryl - ethyl - (ethylthioethyl) thiophosphate by treating the potassium salt of tetrahydrofurfurylethyl - thiophosphoric acid <FORM:0814198/IV (b)/5> with b  - chloro - diethyl sulfide; (2) benzyl-ethyl - (ethylthio - ethyl) thiophosphate from benzyl-ethyl-potassium thiophosphate and b -chloro - ethyl - ethyl sulphide or by transesterifying diethyl phosphite with b -hydroxydiethyl-sulphide and converting with sulphur and K2CO3 and treating the product with benzyl chloride; (3) cyclohexyl-ethyl-(ethyl thio ethyl) thiophosphate from b -chloro diethyl sulphide and cyclohexyl ethyl-potassium thiophosphate; (4) the addition product of sulphur and benzyl ethyl-(b -ethyl-thioethyl) phosphite; (5) the addition product of sulphur and parachlorobenzyl-ethyl-(ethyl-thioethyl) phosphite.ALSO:Pesticidal preparations comprise as active ingredients thiophosphoric acid esters of the general formula <FORM:0814198/VI/1> in which one Z represents sulphur and the remaining Z's represent oxygen, R represents an alkyl radical containing not more than 4 C atoms, R1 represents a cycloaliphatic, e.g. cyclohexyl, araliphatic, e.g. benzyl, or heterocyclic radical free from enolizable ketone or thioketane groups, e.g. tetrahydrofurfural, R2 represents an aliphatic radical which may be substituted with halogen, thiocyanogen, cyano nitro ether or ester groups, and "alkylene" represents an alkylene radical containing not more than 4 C atoms and a solid or liquid diluent or solvent.  Other insecticides and/or fungicides may be incorporated in the composition.  Specified compounds are tetrahydrofurfurylethyl - (ethyl - thioethyl) - thiophosphate, benzyl - ethyl - (ethylthio - ethyl) - thiophosphate, cyclohexyl - ethyl - (ethyl - thioethyl) - thiophosphate, the addition product of sulphur and para - chlorobenzyl - ethyl - (ethyl - thioethyl) - thio phosphite, and the addition product of sulphur and benzyl ethyl-(b -ethyl-thioethyl)-phosphite.